Recently, several proposals for golf balls exhibiting both high ball resilience and soft impact feel have been proposed. An example of a conventional two-piece golf ball is disclosed in Japanese Unexamined Patent Publication No. 1987-270178. In the golf ball of this publication, many depressions and projections are provided on the surface of the core, and the cover and the core are connected to each other through these depressions and projections. In this structure, because the contact between the core and the cover is improved, energy losses when energy is transferred from the cover to the core can be reduced, and ball resilience thereby improved.
In the golf ball disclosed in the above-mentioned publication, because the core and the cover are firmly connected through depressions and projections formed over the entire surface of the core, deformation of the cover in the spherical surface direction when hit is greatly reduced. Therefore, the degree of flexibility in deformation of the cover is reduced and this deteriorates impact feel.